The purpose of this research study is to determine if FTC, given orally once daily together with other anti-HIV treatments, is equally as good as lamivudine. In the past, great progress has been made in understanding Human Immunodeficiency Virus (HIV) infection, how it leads to AIDS, and what treatments work best. Currently, the treatment recommended in US government (NIH) guidelines includes two nucleoside reverse transcriptase inhibitors (NRTI) plus a protease inhibitor (PI) or a Non-Nucleoside Reverse Transcriptase Inhibitor (NNRI). The study drug FTC is an NRTI. It is similar to the approved drug lamivudine (3TC, Epivir). This is an open-label study, which means you and the study investigator will know if you are taking FTC. This is also a randomized study, which means you will be selected by chance to either continue your current treatment or switch to a treatment that replaces lamivudine with FTC.